benchmark of custom indexof vs. a map

benchmark.js

'use strict';

// var fast = require('fast.js');
var Benchmark = require('benchmark');


function generateString(length) {
  var text = "";
  var possible = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789#$%^&*()-_+=!@~<>?/.,[]}{\|}";
  for (var i = 0; i < length; i++) {
    text += possible.charAt(Math.floor(Math.random() * possible.length));
  }
  return text;
}

var things = new Array(10000);

var lookups = new Array(100);

for (var i = 0, j = 0; i < things.length; i++) {
  things[i] = generateString(40);
  //console.log(things[i]);
  if ((i % 100) === 0) {

    lookups[j] = things[i];
    j++;
  }
}

function fastIndexOf (subject, target, fromIndex) {
  var length = subject.length,
      i = 0;

  if (typeof fromIndex === 'number') {
    i = fromIndex;
    if (i < 0) {
      i += length;
      if (i < 0) {
        i = 0;
      }
    }
  }

  for (; i < length; i++) {
    if (subject[i] === target) {
      return i;
    }
  }
  return -1;
};


function mapIt(source, match, key) {
  return source.map(function (el) {
    // if (el[key])
    //   return el[key];
    // else
    return el;
  }).indexOf(match);
}

console.log('done prep');

var suite = new Benchmark.Suite;
var count = 0;
suite.add('fastindexof', function () {
  for (var i = 0; i < lookups.length; i++) {
    var found = fastIndexOf(lookups, lookups[i]);
    if (~found) count++;

  }
})
  .add('mapit', function () {
    count = 0;
    for (var i = 0; i < lookups.length; i++) {
      var found = mapIt(lookups, lookups[i]);
      if (~found) count++;
    }
  })
  .on('cycle', function (event) {
    console.log(String(event.target));
  })
  .on('complete', function () {
    console.log('Fastest is ' + this.filter('fastest').map('name'));
  })
// run async
  .run({ 'async': true });

console.log('done again');